Complex systems, such as aircraft, incorporate many devices that consume electrical power. A challenge is presented when a system may be supported by a power source capable of supplying a maximum amount of power and, at certain points during system operation, the devices may require more than the maximum amount of available power. Some devices may only require power at certain times. Unfortunately, many devices that may only require power intermittently or periodically may seek to consume power at the same time that other devices also require power, thereby resulting in an aggregate power demand in excess of an available supply.
Conventionally, when the demand for power exceeds the available supply, some devices seeking power may not be provided power and some devices currently being provided power may be cut off. Devices may be assigned priority so that devices that may be considered important may not be shut down or may be among the last to be shut down. For example, among aircraft systems, environmental control systems may be accorded a higher priority than galley appliances or on-board entertainment systems. As a result, when the demand for power exceeds the available supply of power, the galley appliances and on-board entertainment systems may be shut down before the environmental control systems may be shut down.
Conventional power distribution systems may be responsive to present demands. Thus, in the foregoing example, although it might be possible to sequentially provide power to either the galley appliances or the on-board entertainment systems so that neither may be abruptly shut down, conventional systems manage only to present demands.